【正文】 s Day. More and more young Chinese people begin to celebrate this day in a very similar way as that in western countries. Fewer people than ever will gaze at the heavens on Saturday to pick out the two stars shining bright on either side of the Milky Way, that is, if people even know on which day Qixi falls. There are ready reminders dotted about, in the form of big ads saying Sales on Chinese Valentine39。 Festival. In this day, girls will throw a sewing needle into a bowl full of water on the night of Qixi as a test of embroidery skills. If the needle floats on top of the water instead of sinking, it proves the girl is a skilled embroiders. Single women also pray for finding a good husband in the future. And the newly married women pray to bee pregnant quickly. Tradition transformed The love story of Niulang and Zhinu, and the Qixi Festival have been handed down for generations. Yet these ancient traditions and customs are slowly dying out. Many modern Chinese, particularly youngsters, seem to know more about St Valentine39。s time for the wild fruits to ripe. The picturesque Arxan in Autumn is indeed a fairyland only exists in a dream that satisfies all your fantasies. If it rains heavily on Saturday night, some elderly Chinese will say it is because Zhinu, or the Weaving Maid, is crying on the day she met her husband Niulang, or the Cowherd, on the Milky Way. Most Chinese remember being told this romantic tragedy when they were children on Qixi, or the Seventh Night Festival, which falls on the seventh day of the seventh lunar month, which is usually in early August. This year it falls on Saturday, August 2. Folklore Story As the story goes, once there was a cowherd, Niulang, who lived with his elder brother and sisterinlaw. But she disliked and abused him, and the boy was forced to leave home with only an old cow for pany. The cow, however, was a former god who had violated imperial rules and was sent to earth in bovine form. One day the cow led Niulang to a lake where fairies took a bath on earth. Among them was Zhinu, the most beautiful fairy and a skilled seamstress. The two fell in love at first sight and were soon married. They had a son and daughter and their happy life was held up as an example for hundreds of years in China. Yet in the eyes of the Jade Emperor, the Supreme Deity in Taoism, marriage between a mortal and fairy was strictly forbidden. He ordered the heaven troop to catch Zhinu back. Niulang grew desperate when he discovered Zhinu had been taken back to heaven. Driven by Niulang39。 ll wait in the line for one hour to get a ticket, and another two hours at the site, to only see a tiny bit of the place due to the crowds. Last year, 428 million tourists traveled in China over the weeklong holiday in October. Traveling during this period is a matter that needs thorough preparation. If you are short on time to plan the uping Golden Week it may not be a bad idea to avoid some of the most crowded places for now. There is always a place so fascinating that everyone yearns for. Arxan is a place like this. The beauty of Arxan is everlasting regardless of the changing of four seasons. Bestowed by nature, its spectacular seasonal landscape and mountains are just beyond word. Arxan is a crucial destination for the remended travelling route, China Inner Mongolia Arxan — Hailar — Manzhouli. It is also the joint of the four prairies across the SinoMongolian border, where people gravitate towards the exotic atmosphere mixed with Chinese, Russian, and Mongolia elements. As a historic site for the Yitian Battle, Arxan still embodies the spirit of Genghis Khan. Walking into Arxan, you will be amazed by a kaleidoscope of geous colors all the year round the Spring azaleas blooming red in the snow, the Summer sea wavering blue in the breeze, the Autumn leaves painted in yellow covering volcanic traces, and the Winter woods shining white on the vast alpine snowscape. Hinggan League Arxan city is situated in the far eastern area of Inner Mongolia Autonomous Region. Its full name Haren Arxan means hot holy water in the Mongolian language. Arxan is a tourism city in the northern frontier with a blend of large forest, grand prairies, vast snowfield, heaven lake cluster, thermium, as well as volcanic cluster. It is a rare and unique ecotourism base filled with healthy sunshine, clean air and unspoiled green. Nestled close to the country39。導師嚴謹?shù)闹螌W態(tài)度、勤奮和謙虛的人品，都對 我 在今后的學習和做人方面都產生有益而深遠的影響，激勵著我在人生的道路上永遠奮進。 西安鐵路職業(yè)技術學院畢業(yè)設計（論文） 17 致 謝 本論文的研究工作是在導師 xxx 的悉心關懷和精心指導下完成的。 通過實踐證明 , 對繼電器 ( 接觸器 ) 觸頭故障原因的分析及采取的相應措施 , 在應用上取得了很好的效果 , 無論在內燃機車及供電系統(tǒng)中 , 對繼電 (接觸器 ) 觸頭故障的處理 , 不但大大減少了機車途中故障 , 也保證了安全可靠供電 , 而且保證了繼電保護的可靠性。靜鐵芯采用彈性固定 接觸式繼電器的觸點接觸失效物理分析 16 總 結 本文針對接觸器式 繼電器的觸點工作可靠性展開研究。 表 2 提高可靠性的措施和方法 待解決的問題 方法措施 減小與穩(wěn)定接觸 電阻 一方面接觸力將接觸斑點擠壓變形 ,增大接觸面積 ,同時使得接觸斑點的個數(shù)增加 ,這樣接觸力越大 ,接觸電阻越小 。針對接觸電阻引起的接觸不良或靜熔焊 , 應采取有效措施減小與穩(wěn)定接觸電阻 。再則在分磁環(huán)的固定方面，應采用更為牢固的鉚接技術，使其不會在機械振動時脫落，而造成損壞試品的情況 [31]。 (2)通過嚴格生產中的工藝水平，消除機械部件的毛刺，以及觸點表面的雜質、灰塵 與有機分解物的污染 。選擇的材料化學穩(wěn)定性高，抗污染和抗腐蝕的能力強，就不易產生有機膜 [30]。 （ 2）選擇合適的觸點接觸形式：選擇接觸面較小接觸壓強較大的接觸形式。然而增加觸點接觸力，會增加電磁系統(tǒng)的尺寸，增加產品的功率損耗 [29]。 接觸式繼電器的觸點接觸失效物理分析 14 第五章 改善接觸器式繼電器接觸不良的措施 接觸器式繼電器的主要失效模式是觸點間接觸不良，觸點間過大且不穩(wěn)定的接觸電阻 [28]。如負載既有感性負載 , 也有電阻負載 ,這可采用兩端并聯(lián)措施 , 斷開時將能量消耗在并聯(lián)回路中。然后再使用繼電器最低動作電壓 ( 電流 ) 檢查是否可靠吸合、分斷 , 觸頭壓力是否過低 , 若是 ,則應進行適當調整 , 若不是 , 則應根據(jù)負載容量核實繼電器的各項承載能力 , 如負荷過大 , 一是調整負載容量 , 二是更換容量較大的繼電器 [27]。 西安鐵路職業(yè)技術學院畢業(yè)設計（論文） 13 第四章 繼電器 ( 接觸器 ) 觸頭故障處理方法 (1) 對觸頭接觸不良、不牢固 , 檢查時發(fā)現(xiàn)這類故障 , 千萬不要用砂紙磨 , 可將觸頭表面用小 挫輕輕挫去毛刺 , 然后可用綿紗沾酒精或四氯化碳溶液擦掉臟物 , 處理后檢查觸頭及有關參數(shù) , 達到標準 , 再投入運行。 。 。 工藝結構不當引起的失效